Denis J. O'Connell (January 28, 1849 – January 1, 1927) was an Irish-born American prelate of the Roman Catholic Church. He served as bishop of the Diocese of Richmond in Virginia from 1912 to 1926. He previously served as an auxiliary bishop of the Archdiocese of San Francisco in California from 1908 to 1912. Before becoming a bishop, O'Connell served as rector of the Pontifical North American College in Rome, then rector of the Catholic University of America in Washington, D.C.